Factors Limiting the Cathodic Current on Painted Steel

Abstract

The cathodic properties of painted steel specimens exposed to air‐saturated artificial sea water have been examined. The painted steel was cathodically polarized by galvanic coupling to freely exposed steel. Both the magnitude of the cathodic current and the change with time were found to depend on the paint used. The cathodic current is most probably limited entirely by the paint film resistance. The magnitude of the resistivity was found to vary from 109 Ω‐cm to 1013 Ω‐cm.